The present invention relates to an image scanning apparatus and more particularly to a dual transmissive/reflective image scanning apparatus with protective apparatus.
Typically, there are three main categories of image scanning apparatuses including transmissive scanners for scanning transparent originals such as slides and transparencies, reflective scanners for scanning opaque originals such as documents and photographs, and transmissive/reflective scanners for scanning both transparent originals and opaque originals.
A conventional transmissive/reflective scanner includes a glass platen upon which either a transparent original or an opaque original is placed. When scanning the transparent original, a light source from the original cover illuminates through not only the transparent original but also the glass platen. Usually the original cover provides another glass platen on one surface, and this glass platen is in touch with the original when scanning. However, glass may cause reflection and refraction, and loss of light is resulted as light passes through. Additionally, greasy dirt and dust easily gather on the glass platen during use. When original is placed upon or retrieved from the glass platen, the glass platen is easily smudged. With the conventional scanner, only dirt or dust deposited on the upper surface of the glass platen is allowed to be cleaned. That deposited on the lower surface of the glass platen can not be cleaned because the glass platen is not allowed to be taken out from the housing. Moreover, with the design of two glass platens, image deformation may bring about as the transparent original is placed between the two glass platens which are not substantially parallel to or contact tightly to each other.
A transmissive/reflective image scanning apparatus has been disclosed in U.S. Pat. No. 5,574,274. It provides a light source within the inner of the housing instead of within the original cover for transmissive scanning purpose. Although some of the problems have been solved, it leads to a higher manufacturing cost due to the complication of the light travelling pathway.
In order to solve the aforementioned problems, the present invention provides two types of trays, which are used for transparent originals or opaque originals respectively. When scanning transparent objects, no glass is present on the housing so that the light source only passes through the glass of the original cover. Therefore, a high scanning quality is achieved.
However, the image scanning apparatus of the present invention has a cavity defined on the upper surface of the housing. When the original cover is in an open state and the cavity is not protected, external objects or dust may enter the housing via the cavity.
The present invention further provides a protective apparatus, which prevents the external objects of dust from entering the housing via the cavity.
The present invention relates to an image scanning apparatus and more particularly to a dual transmissive/reflective image scanning apparatus with protective apparatus. The present invention provides a tray of a first type for reflective scanning and a tray of a second type for transmissive scanning.
The present invention has a slot within which the tray of the first type or the tray of the second type may be selectively inserted. The tray of the first type is inserted within the slot for reflective scanning, while on the other hand, the tray of the second type is selectively inserted within the slot for transmissive scanning. When scanning transparent originals, a light source from the original cover passes directly through the transparent originals. Since the light passes through only one glass platen, loss of light is lower than the prior art. Furthermore, either the tray of the first type or the tray of the second type is allowed to be withdrawn from the housing for cleaning purpose.
The purpose of the present invention is to provide a protective apparatus to prevent external objects and dust from falling into the housing avoiding damage to the components inside the housing. The protection apparatus includes a first device, a second device, and a third device. The first device is provided inside the housing. The tray of the first type has the second device for selectively coupling with the first device. The original cover provides the third device for selectively coupling with the first device. The original cover is not allowed to open as the tray of the second type is inserted within the slot, whereas the original cover is allowed to open as the tray of the first type is inserted within the slot. As the original cover is open, the tray of the first type is not allowed to be withdrawn from the slot. However, as the original cover is closed, the tray of the first type or the tray of the second type is allowed to be withdrawn from the slot.